This invention relates to instruments for taking samples and has particular use as a medical instrument for taking cultures from minute channels in the human body.
In taking biological samples, swabs comprising stems having absorbent material affixed thereto at one end have long been used. However, absorbent materials, such as cotton is generally too wide for convenient use in minute channels in the body, such as a urethra. Such materials progress along a urethra only with difficulty, and cause significant discomfort and pain to a patient.
To avoid the problems of cotton swabs, physicians have relied on bacteriological wires with or without loops formed at the ends. Such wires are non-disposable and thus require sterilization before each use. The use of a straight wire presents a significant risk of puncturing the urethra with a sharp, unguarded tip of the wire. A puncture aids the spread of bacteria and fungi, and may result in the formation of a suburethral abscess or stricture of the urethra. The risk of puncture is increased by the inflexibility of the wire. In addition to the dangers of bacteriological wires, the sharp unguarded tip on the inflexible wire causes pain to the patient. Finally, because of the small diameter of the wire and the lack of a specialized tip, very small samples are obtained for culture and/or staining.
It is therefore an object of this invention to provide an instrument for taking samples from minute channels in the human body without causing undue pain or physical damage to a patient. It is a further object of this invention to provide an instrument for taking samples having a minute, specialized tip.
It is also an object of this invention to provide an instrument for taking samples which is sufficently flexible for following extended channels.
It is a further object of this invention to provide an instrument for taking samples which is inexpensive and thus disposable to eliminate the requirement for sterilization of the instrument after use.
After taking a sample, a physician generally prefers to immediately streak the culture across Thayer-Martin agar plates. The agar may be contained in transgrow bottles; hence, a stem of several inches facilitates the streaking process. And a stem of several inches is generally required in the taking of a sample from the urethra or like channel.
When an agar plate is not immediately available, a sampling instrument must be placed in a small vial of thioglycollate transfer medium. A stem sufficiently long for taking a sample and streaking the sample in a transgrow bottle is generally too long to be carried in the usual transfer vial. To overcome this problem, the use of detachable handles on short stems has been suggested. An example of such a device is found in Boettger (U.S. Pat. No. 2,835,246) However, in Boettger, the handle is too wide to be inserted into many body channels. Hence, the problem of providing a long stem for insertion into a body channel which is compatible with the use of small transfer vials still exists. It is a further object of this invention to provide an instrument for taking samples which solves this problem.